The common causes of pain in the lateral thigh root are greater rotor bursitis, iliotibial bundle friction syndrome, and lateral femoral dermatomal neuritis, as follows: First, greater rotor bursitis: if you feel the highest bone in the lateral thigh, there is pain at the tip of the bone, and the pain increases at night when the affected side is lying down, and there is pain when you press the part of the bone protrusion with your hand, it means greater rotor bursitis. Second, the iliotibial bundle friction syndrome: in the lateral thigh there is a muscle called the iliotibial bundle, the iliotibial bundle is cold or traumatized, contracture occurs, there will be pain in the lateral thigh root. Thirdly, lateral femoral cutaneous neuritis: fever, tingling or anthroposis in the lateral thigh, that is, the feeling of crawling insects, may be the lateral femoral cutaneous nerve inflammation, mainly due to the lateral femoral cutaneous nerve out of the pelvis part of the compression caused by.